Mini-Nut Propagation Technique of Kola (Cola nitida, (Vent.) Schott and Endl.): Prospects for Germination and Propagation of Kola Plantlets in the Pre-Nursery

摘要

Limitations against propagation of Cola nitida include pronounced dormancy of between 1 and 8 months after sowing (MAS) leading to uneven germination and seedling growth. This experiment was conducted in a screenhouse. Federal University of Agriculture Abeokuta, Nigeria, to evaluate the effects of mini-nut and nut-color on germination and seedling growth of C. nitida nuts. The experiment was in a completely randomized design replicated 3 times. Treatments comprised two factors: nut/seed-colored biotype (white, pink, and red) and mini-nut (embryonic portion of cotyledon) [excised embryonic portion cotyledon (EEPC), 25% embryonic portion cotyledon (EPC), 50% EPC, 75% EPC, and 100% EPC (whole nut/ seed)], giving 15 treatment combinations-sown in plastic cups of 50 cl filled with sawdust. Germination percentage and morphological growth of plantlets (plant height (cm), number of leaves, dry matter yield (g/plant)) were monitored; data subjected to analysis of variance and mean comparisons done (p < 0.05). As early as 4 WAS, the EEPC and 25% EPC had 67.78% and 54.44% germination, respectively. Within the same period, 51.33%, 48.00%, and 31.33%, respectively, of white-, pink-, and red-colored seeds germinated. At 6 WAS, the white-, pink-, and red-coloredseeds had mean germination of 80.67%, 92.00%, and 72.67%, respectively. At 12 WAS, germination was observed to complete with the pink-, red-, and white-colored nuts having 97.33%, 92.61%, and 91.33%, respectively. Within the same period, the mini-nut sizes had between 92.22% and 95.56% germination. Combining the two factors, 50% EPC, 25% EPC, and EEPC of white-nut biotype germinated earliest with 50.00-76.67% at 4 WAS and 73.33-80.00% at 5 WAS. The EEPC of pink-colored biotype attained 100% at 6 WAS, while other treatments were between 56.67% and 93.33%. Thus, while earliness in germination pattern follows the order: EEPC > 25% EPC > 50% EPC > 75% EPC > whole nut, the plantlet morphological growth followed a reverse order. With mini-nut technique therefore, timely and even germination of kola nuts were obtained and 50%EPC would.